Updated

Republican Sen. Kit Bond of Missouri is following on the heels of Norm Coleman of Minnesota, offering his endorsement of Rudy Giuliani in a Friday announcement in Washington, D.C., FOX News has learned.

Bond, who serves as the ranking member of the Senate Intelligence Committee, and Coleman bring the total number of senators endorsing Giuliani to three, trailing rivals Mitt Romney and John McCain in Senate endorsements. Sen. David Vitter of Louisiana endorsed Giuliani months ago.

The two endorsements could boost the former New York City mayor's presidential bid in key states. Minnesota is a traditional swing state, and is the place where the Republican National Convention is being held in early September 2008.

Coleman, a Republican incumbent facing a tough re-election next November, entered the U.S. Senate in 2003, replacing Paul Wellstone, who died in a plane crash shortly before the 2002 election. He is the former mayor of St. Paul.

On Thursday, he issued a statement offering his support of the Republican presidential frontrunner.

"I have long respected and admired Rudy Giuliani," said Senator Coleman. "Rudy Giuliani and I share a strong bond as former mayors. We focused on bringing people together to get things done, and to ensure that our focus was on solutions, not problems. I am confident that his vision and his strength as a candidate will give Republicans a strong voice in the November 2008 elections."

Bond's endorsement — to be made formal in an 11 a.m. E.T. announcement — could bolster Giuliani's standing in the Show Me State, where voters go to the polls on Feb. 5, a.k.a. "Tsunami Tuesday."

Giuliani is competing in the traditional primary states of Iowa, New Hampshire and South Carolina but has made Feb. 5 — the date set for nearly two dozen states to hold votes — a key part of his primary strategy.

FOX News' Mosheh Oinounou contributed to this report.