Congressman Tom Tancredo (R-Littleton) announced last night that he would not be running for re-election in 2008. Tancredo is currently running for President, and given that he has as much chance of living in the White House in 2009 as you or I, his days in politics would appear to be numbered.

Tancredo’s departure is certain to lead to a busy Republican primary in CO-6, because like CO-5 last summer, the primary winner is more than likely going to roll over the opposition in the general election. Republican voters outnumber Democrats by a nearly 2-to-1 margin in CO-6, which is roughly made up of Southern Jefferson County and all of Douglas County (in other words, everything within a 2-3 mile radius of C-470), and several elephants have been quietly preparing for a congressional campaign for months. State Sens. Tom Wiens and Ted Harvey will likely announce their candidacies sometime soon, and Wil Armstrong (son of former U.S. Sen. Bill Armstrong) may also jump into the race shortly.

Several other Republicans could join the fray soon, among them Secretary of State Mike Coffman, who is one of the most interesting potential candidates in CO-6. If Coffman runs for congress and wins, which is a strong likelihood given his great name recognition after three statewide campaigns, then the office of Secretary of State will be filled by Gov. Bill Ritter…and it would almost assuredly be a Democrat who got the job.

A similar scenario played out in 2002 when then-Attorney General Ken Salazar defeated Pete Coors for the U.S. Senate. The AG post was filled by then-Gov. Bill Owens, who nominated Republican John Suthers for the job. In 2002 Democrats gladly exchanged the office of AG for the more influential and prestigious U.S. Senate seat, but Coffman is in a different position. In Coffman’s case, Republicans don’t need him to run in order to keep CO-6 in elephant hands; whoever wins the GOP primary will likely win the general election. But on the other hand, Coffman is the probable favorite should he decide to run, so it will be hard for him to resist the siren song of the more intriguing job of congressman.

Democrats have a similar situation in CO-6, but to a much lesser degree. The most well-known elected Democrat in CO-6 is probably State Rep. Joe Rice, whose victory in 2006 was one of the surprises of the season given that his district, HD-38, is traditionally represented by a Republican. Rice would probably be the Democrats’ toughest candidate in CO-6, but for all of his virtues, he would still be a heavy underdog to the Republican nominee. The question for Democrats then becomes this: Do you run Rice, who might be your best candidate, and risk losing his state House seat on a long shot bid for congress? It would certainly be a fair trade for Democrats to give up a state House seat in order to gain a seat in congress, but Rice wouldn’t be the same favorite to win as Coffman would be; and without Rice as an incumbent, the Dems would be hard-pressed to keep control of HD-38.

Coffman and Rice will be interesting candidates to watch as the race for CO-6 heats up, because their potential candidacies could create a chain-reaction of events that could alter Colorado’s political landscape.