Democratic Rep. Harold Ford is running even with Republican Bob Corker in Tennessee, while Democrat Jon Tester has edged ahead of Sen. Conrad Burns in Montana, according to polls released Sunday for some of the most contested Senate races.

The findings suggest an intensely competitive campaign for Congress heading into the Nov. 7 elections.

Republican Sen. Mike DeWine is in a virtual tie with Democratic Rep. Sherrod Brown in Ohio.

The three races are three that Democrats need to win if they are to take control of the Senate.

The Mason-Dixon polls done for various media outlets found:

—Ford had the backing of 43 percent in Tennessee, while former Chattanooga, Tenn., Mayor Corker was backed by 42 percent. Corker had a lead in midsummer polling matching the two.

—Tester has pulled ahead of Burns in Montana, by 47 percent to 40 percent. They were tied in August polling.

—Brown had 45 percent and DeWine had 43 percent in Ohio, findings similar to those of a Quinnipiac poll released a week ago.

The polls were conducted for MSNBC, McClatchy Newspapers and newspapers in each of the states — The (Cleveland) Plain Dealer, the Lee Newspapers in Montana and The Commercial Appeal of Memphis, Tenn., and Chattanooga Times Free Press in Chattanooga, Tenn.

The polls of 625 registered voters in each state were conducted Sept. 25-28. They had margins of sampling error of plus or minus 4 percentage points.