Democratic Sen. Mark Udall of Colorado last Wednesday was considered better-than-even money to win a second term, but he was regarded as even money at best by Thursday, after Rep. Cory Gardner joined the Republican primary field.
With the surprise entrance of Gardner, Udall now faces the strongest possible opponent the Centennial State GOP could offer.
This sudden change in the political picture of a state that passed fresh gun-control legislation and legalized marijuana last year is dramatic.
Republicans came up with their strongest possible threat to Udall, son of the late Arizona congressman Mo Udall, raising the odds on the GOP winning the "magic six" — the six seats they need to turn their 45-seat minority in the Senate into a majority.
To make matters easier for Republicans, another conservative who had been in the Senate race immediately dropped out after Gardner's entry.
Ken Buck, former Weld County district attorney and narrow loser to Democratic Sen. Michael Bennet in 2010, told reporters he was running for Gardner's now-open Fourth Congressional District seat instead.
Moreover, another Republican Senate hopeful, state Rep. Amy Stephens, bowed out of the race last week in favor of Gardner.
"The scene of candidates suddenly abandoning their campaigns when someone gets in late is something of a phenomenon," Greg Walcher, former Colorado Natural Resources secretary and a former GOP U.S. House nominee, told Newsmax. "Usually, it's the other way around: Candidates dig in their heels and say they are not going to defer to someone who is suddenly anointed."
Another GOP hopeful, state Sen. Owen Hill, denounced Gardner's sudden entrance into the race and vowed to remain a candidate in the June 24 primary.
For at least a year, state and national party leaders had been working hard to woo Gardner, 39, into the Senate race. A former state legislator and two-term U.S. House member, the conservative Gardner is considered one of his party's best prospects for statewide office.
"Cory is the natural heir in a line that includes Bill Armstrong, Hank Brown, and Wayne Allard — all Republican House members who went on to the Senate because they knew how to sell their conservatism," former state GOP Chairman Dick Wadhams told Newsmax.
Nationally syndicated columnist George Will agreed, writing recently that "Gardner, who has a solid conservative voting record but does not have a serrated edge, is suited to purple Colorado."
Even before Gardner’s surprise entry into the race, 63-year-old Udall had been considered on shaky political ground because of his down-the-line support for Obamacare.
According to a Quinnipiac Poll of likely voters conducted in February, 60 percent of Coloradans oppose Obamacare.
The same poll showed Udall defeating Buck, then considered the GOP front-runner, by a tight margin of 45 percent to 42 percent.
Udall would also have tough contests against other Republicans, with narrow margins against Stephens (43 percent to 41 percent), Hill (44 percent to 39 percent), and state Rep. Randy Baumgardner, who's also in the GOP race (43 percent to 41 percent), Quinnipiac found.
With those figures, both National Republican Senatorial Committee Chairman Jerry Moran of Kansas and Colorado State GOP Chairman Ryan Call began working vigorously to get Gardner to switch from a planned House re-election bid to a Senate race.
On Thursday, their efforts bore fruit as Gardner announced his candidacy for the Colorado Senate seat.
On Monday, former Rep. Bob Beauprez, the 2006 gubernatorial nominee, became the seventh Republican to seek the nomination to run against Democratic Gov. John Hickenlooper. But for now, Udall's survival is the biggest concern of state Democrats.
Democratic Rep. Dianna DeGette of Colorado said as much in a fund-raising letter last week: "Yesterday the ground shook for Colorado Democrats. This is a must-win race for Democrats, and Gardner jumping in means two things: 1. We can't take any seat for granted. 2. We can't wait to mobilize."
John Gizzi is chief political columnist and White House correspondent for Newsmax.
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