By all accounts, the Democrats' five-seat majority in the Colorado State Senate is safe, but either party could gain a couple seats during this year's election.

The key Senate districts to watch are the 8th state Senate District, the 16th District, the 19th District, the 23rd District and the 26th District. Of those, two are open seats being relinquished by Republicans, one has a Republican incumbent, one has a Democratic incumbent, and one is being vacated by a Democrat.

Only competitive state Senate seats are profiled. Democrats Rollie Heath and Peter Groff are running unopposed in Districts 18 and 33, respectively.

4th STATE SENATE DISTRICT

OPEN SEAT: State Sen. Tom Wiens (R-Castle Rock) has declined to seek re-election

Candidates:

• Joe Alsup (Democratic): Architect from Larkspur
• Mark Scheffel (Republican): Attorney and former Douglas County Republican Party Chair from Parker

Overview:  The 4th District was designed for Scheffel to run in 2004, though he dropped out then when Wiens entered the race. Registered Republicans in the district outnumber registered Democrats and registered unaffiliateds combined.

What to look for: Scheffel will finally take a seat in the Statehouse, four years later than expected.

8th STATE SENATE DISTRICT

OPEN SEAT: State Sen. Jack Taylor (R-Steamboat Springs) is term-limited

Candidates:

• Ken Brenner (Democratic): Former Steamboat Springs City Council president
• Al White (Republican): State representative from Hayden

Overview: A few insiders offered this race as the "dark horse" to watch for a potential upset by Brenner. But others -- from both parties -- give the edge to White because he's known and well-liked as a state representative. Registered Republicans outnumber registered Democrats district-wide, but many of the mountain towns are liberal enclaves.

What to look for: How things go in Eagle County. It's the most populous county in the district, Republican/Democratic voter registration is nearly equal there, and (except for the 2nd Congressional District race) every race from president down to county commissioner is competitive.

10th STATE SENATE DISTRICT

Incumbent: State Sen. Bill Cadman (R-Colorado Springs)

Candidates:

• Bill Cadman (Republican): State senator from Colorado Springs
• Diane Whitley (Democratic): Paulsboro Environmental Commission Chair from Calhan

Overview:  With registered Republicans making up about half the registered voters in the district, Cadman's got a pretty safe seat. This is Cadman's first state Senate election: he took over for Ron May in October 2007.

What to look for: Cadman won at least 65 percent of the vote during his four terms in the state House, and it's not unreasonable to think he could keep the streak going in the state Senate.

12th STATE SENATE DISTRICT

OPEN SEAT: Senate Minority Leader Andy McElhany (R-Colorado Springs) is term-limited

Candidates:

• Keith King (Republican): Former state House Majority Leader from Colorado Springs
• Pete Lee (Democratic): Attorney and business owner from Colorado Springs

Overview:  As a Colorado Springs Gazette story headline stated: "This was supposed to be easy." In a solid conservative-leaning district, Lee's relatively strong fundraising and hard work have made him surprisingly competitive against King, who left the state House of Representatives in 2006 because of term limits. King has turned many district residents off because of his brusque, polarizing style. But in a district where only 25 percent of registered voters are Democrats, Lee will be hard-pressed to pull out a win.

What to look for: A perfect storm. That's what it would take for Lee to pull out a win.

14th STATE SENATE DISTRICT

Incumbent: State Sen. Bob Bacon (D-Fort Collins)

Candidates:

• Bob Bacon (Democratic): State senator from Fort Collins
• Matt Fries (Republican): Businessman from Fort Collins

Overview:  When Bacon was elected to the seat four years ago, registered Republicans in Senate District 14 outnumbered registered Democrats by about 6,000 voters. Today, there are 3,000 more registered Democrats in the district that there are Republicans. With this major shift, the incumbency advantage, plus coattails from top-ticket Democratic candidates, Bacon should have little trouble keeping his seat.

What to look for: If voters turning out for the presidential, U.S. Senate or congressional races get far enough down the ballot to reach the state Senate race.

16th STATE SENATE DISTRICT

Incumbent: State Sen. Dan Gibbs (D-Silverthorne)

Candidates:

• Dan Gibbs (Democratic): State senator from Silverthorne
• Don Ytterberg (Republican): Businessman from Evergreen

Overview:  It's the Republicans' best hope of knocking off a Democratic incumbent in any state Senate race this year. Ytterberg (pronounced "IT-erberg" ) has worked hard and stands a chance of hanging in there on election night. Gibbs, appointed to replace Joan Fitz-Gerald in 2007,

What to look for: As in many other districts, a good Democratic year nationwide could raise Gibbs' boat.

17th STATE SENATE DISTRICT

Incumbent: Assistant Senate Majority Leader Brandon Shaffer (D-Longmont)

Candidates:

• Brandon Shaffer (Democratic): Assistant Senate Majority Leader from Longmont
• Katie Witt (Republican): 2008 Mitt Romney presidential campaign state director from Longmont

Overview: Insiders expect Shaffer to win re-election without much of a problem. If he wins, Shaffer is likely to become the Senate Majority Leader next session.

What to look for: If Betsy Markey loses this year, will Shaffer be too content as Majority Leader to consider another try at the 4th Congressional District seat in 2010?

19th STATE SENATE DISTRICT

OPEN SEAT: State Sen. Sue Windels (D-Arvada) is term-limited

Candidates:

• Evie Hudak (Democratic): Colorado State Board of Education member from Westminster
• Libby Szabo (Republican): Mortgage broker from Arvada

Overview:  Along with Senate District 26, the fight between Hudak and Szabo has been the most-watched state Senate race this election cycle. Republicans slightly outnumber Democrats in the district, but it's the unaffiliateds that will decide this election. There's been lots of 527 involvement on both sides

What to look for: Barack Obama's coattails. If the Democratic surge is large enough, it  can pull Hudak over the top.

21st STATE SENATE DISTRICT

Incumbent: State Sen. Betty Boyd (D-Lakewood)

Candidates:

• Betty Boyd (Democratic): State senator from Lakewood
• Natalie Menten (Republican): State House District 26 GOP Chair from Lakewood

Overview:  Insiders don't consider Boyd vulnerable in this race. A former state representative appointed to the state Senate in 2006, Boyd has name recognition and a fundraising advantage over Menten.

What to look for: Boyd to win

23rd STATE SENATE DISTRICT

Incumbent: State Sen. Shawn Mitchell (R-Broomfield)

Candidates:

• Shawn Mitchell (Republican): State senator from Broomfield
• Joe Whitcomb (Democratic): Attorney from Westminster

Overview: A month ago, it looked like Democrats had a real shot at toppling Mitchell. The race isn't in the bag yet, but many Democrats have grown skeptical about Whitcomb's chances. Last month, pro-Republican 527 groups sent out mailers about how Whitcomb had three restraining orders issued against him in 1995 by an ex-girlfriend (the woman said Whitcomb never threatened her and the charges were dismissed). However, with Weld County being ground zero for the Barack Obama, Mark Udall and Betsy Markey campaigns - and the accompanying barrage of ads and canvassers -- Whitcomb should get some coattails from the top of the ticket.

What to look for: Turnout, especially among unaffiliateds. The higher it is this year, the better it will be for Whitcomb.

25th STATE SENATE DISTRICT

OPEN SEAT: State Sen. Stephanie Takis (D-Aurora) is term-limited

Candidates:

• Robert Hadfield (Republican): Web designer from Thornton
• Mary Hodge (Democratic): State representative from Brighton

Overview:  Hadfield - a former rock musician until he settled down to raise a family -- has run an energetic campaign, but the money hasn't been there for him to be competitive. Hodge, who's term-limited in the state House, also has name recognition in the most populous parts of the district.

What to look for: If Hadfield will try at elective office in the future.

26th STATE SENATE DISTRICT

OPEN SEAT: State Sen. Steve Ward (R-Littleton) declined to seek re-election to run for Congress

Candidates:

• Lauri Clapp (Republican): Former state representative from Centennial
• Linda Newell (Democratic): Business consultant from Littleton

Overview: Democrats are smelling blood in a district that until recently had been solidly Republican. Part of the reason is shifting demographics: Democrats and moderate Republicans have been moving into the district. Clapp has made few campaign appearances (she doesn't even appear in her TV ad), allowing first-time candidate Newell's attacks on Clapp's legislative record to go unrebutted. But Republicans are still the single largest voting group in the district.    

What to look for: Whether the district has trended too far towards the Democrats to elect Clapp.

27th STATE SENATE DISTRICT

Incumbent: State Sen. Nancy Spence (R-Centennial)

Candidates:

• Nancy Spence (Republican): State senator from Centennial
• Nathan Wilkes (Democratic): Telecommunications businessman from Englewood

Overview:  Spence's seat is considered safe.

What to look for: Spence to be re-elected.

28th STATE SENATE DISTRICT

Incumbent: State Sen. Suzanne Williams (D-Aurora)

Candidates:

• Sueyuna Duthie (Republican): Writer and educator from Aurora
• Suzanne Williams (Democratic): State senator from Aurora

Overview:  Duthie hasn't been able to compete with Williams in terms of resources (Williams has outraised her 6-1) - that's not good against an incumbent in a district that leans Democratic. Libertarian Ken Wyble dropped out of the race in mid-October and threw his support behind Duthie, but observers say they have little doubt Williams will win.

What to look for: Williams to win re-election

29th STATE SENATE DISTRICT

OPEN SEAT: State Sen. Bob Hagedorn (D-Aurora) is term-limited

Candidates:

• Suzanne Andrews (Republican): Child nutrition specialist from Aurora
• Morgan Carroll (Democratic): State representative from Aurora

Overview:  Carroll was unexpectedly bumped up to this race from her House District 36 re-election campaign in February after former state Rep. Michael Garcia (D-Aurora) dropped out following allegations that he exposed himself to a lobbyist. Carroll's name recognition, 88-1 fundraising advantage, and 2.2-1 Democrat-Republican voter registration ratio make this an easy race for her to win.

What to look for: Carroll to win it

31st STATE SENATE DISTRICT

Incumbent: State Sen. Jennifer Veiga (D-Denver)

Candidates:

• William Leslie (Republican) from Denver
• Jennifer Veiga (Democratic): state senator from Denver

Overview:  Veiga, who ran unopposed for the seat in 2004, shouldn't have much more of a challenge this year. Registered Democrats outnumber registered Republicans in the district by almost a 3-1 margin. Lane has raised a grand total of $400 - less than what Veiga's campaign spent in one week last month on slate cards and stamps to the Adams County Democratic Party. Plus, Veiga has received goodwill for sponsoring successful legislation this year to allow Sunday liquor sales.

What to look for:  A Veiga victory

35th STATE SENATE DISTRICT

OPEN SEAT: Senate Majority Leader Ken Gordon (D-Denver) is term-limited

Candidates:

• Joyce Foster (Democratic): Former Denver City Council president from Denver
• Bob Lane (Republican): financial services firm owner from Denver

Overview: A quick look at voter registration and fundraising figures illustrates how Foster will easily win. Party registration within the district favors Democrats over Republicans by a 1.7-1 ratio. Foster, thanks to a primary battle with state Rep. Alice Borodkin (D-Denver), has raised $131,254. Lane has raised $10,329.