Gearing up for his fourth -- and what could prove to be his most difficult -- campaign, Sen. Bob Bennett drew the endorsement of the architect of the Republicans' last takeover of Congress: Former House Speaker Newt Gingrich.

"The best thing Utah can do to stop [President Barack] Obama and get conservatism back on the march is re-elect Bob Bennett," said Gingrich, who led the 1994 GOP election surge.

If Republicans fail to oppose the Obama administration, Gingrich said, "we're going to become a secular, socialist system run by a machine."

But, Gingrich said, it's not just about stopping the Democrats.

"For effective conservatives to really govern America, you've got to have solutions," he said. "Yes, you've got to fight with this hand but you'd better have solutions in this hand."

Bennett argued voters should return him to Washington so he can help reform the out-of-control Medicare, Medicaid and Social Security entitlement systems and oppose the Obama administration.

Bennett also said he was backing off on his "Healthy Americans Act," a bipartisan health care plan he was pushing with Oregon Democratic Sen. Ron Wyden, which was scorned by Utah's conservatives and the Tea Party movement.

"The atmosphere in the Senate is so toxic it's not time to put anything forward on health care right now," Bennett said.

Since winning the GOP nomination in a hard-fought, expensive contest in 1992, Bennett has coasted to re-election without serious challenge. This time, Bennett not only faces a handful of scrappy challengers, he is also contending with a deep-seated animosity among Republican faithful toward Washington.

Where Bennett's advertisements during his previous campaigns were light-hearted and poked fun at the senator's height, ears and bald head, this time his posters and fliers show a stern-faced Bennett under the slogan "The Fight Is Now."

"There's no question, if you've been in office [in recent years] you have to bear some of the blame," Gingrich said. "He has to come home and he has to convince people he's part of the solution, not part of the problem."

But Gingrich said Bennett's work opposing the Obama administration's health reform and stimulus spending shows he has "played a substantial role in a situation where the Republicans were badly outnumbered."

A recent poll conducted for The Salt Lake Tribune found 72 percent of Republican voters approve of the job Bennett has done and 46 percent say that, if the GOP primary were held today, they would vote for Bennett; 27 percent say they would support someone else and an equal number are undecided.

However, Bennett's campaign recognizes the risk and the senator has spent more than $2.2 million to try to solidify his support among GOP delegates.

He is being challenged by prominent Salt Lake City attorney Mike Lee, businessman Tim Bridgewater, longtime conservative activist Cherilyn Eagar, and businessman James Williams.

Businessman and restaurateur Sam Granato is the only Democrat who has declared his candidacy.