Greg Orman
Independent Senate candidate Greg Orman and his wife, Sybil, leave from a visit to a campaign phone bank in Shawnee, Kansas, Monday, Oct. 27, 2014. Reuters

Iowa’s Republican candidate has a slight lead, the Kansas race is even tighter and in Michigan the Democrat has a comfortable 15-point cushion over his Republican rival, according to the latest Senate polls. Kansas and Iowa are among the battleground states that will decide which party controls the Senate after Tuesday’s midterm elections.

Iowa state Sen. Joni Ernst is leading Democratic Rep. Bruce Braley, 49 percent to 45 percent, according to a Quinnipiac University poll released Thursday. Ernst’s lead is just outside the survey’s 3.4 percent margin of error. Ernst is considered more likable than Braley and is winning over men by a greater margin than the Democrat’s advantage over her with women, the poll found.

"As Election Day nears, state Sen. Joni Ernst is closing in on Iowa's open U.S. Senate seat. Her lead over U.S. Rep. Bruce Braley inches up to 49-45 percent, giving her the momentum with less than a week left in the campaign," said Peter A. Brown, assistant director of the Quinnipiac Poll. "Nothing is for sure, but one would certainly rather be in her shoes this morning than Braley's. One piece of good news for the Democrat is that he has a 21-point lead among those who already have voted."

The two are competing for the seat of retiring Democrat Tom Harkin, so an Ernst victory would be a Republican gain.

In Kansas, independent candidate Greg Orman is in a statistical dead heat with Republican Sen. Pat Roberts, who is in grave danger of losing his seat. Orman leads Roberts, 44 percent to 42 percent, in a Survey USA poll released Tuesday. The independent’s advantage is within the poll’s 4 percent margin of error. Orman has said he would caucus with whichever party holds the majority in the Senate. The Democrats withdrew their candidate, Chad Taylor, to help Orman.

In Michigan, Democratic Rep. Gary Peters has opened up a 15-point lead over Republican Terri Lynn Land, 50 percent to 35 percent, according to an EPIC-MRA poll released Thursday. President Barack Obama, who has shied away from appearing with Democratic candidates, especially in red states, is scheduled to campaign with Peters on Saturday. Michigan is a blue state that voted for Obama in 2008 and 2012, and for every Democratic presidential candidate since 1992. Peters and Land are vying for the seat of retiring Democrat Carl Levin.