“The GOP’s political machine is kicking into overdrive to save a Senate seat in Kansas that’s suddenly complicating its path to the majority,” Politico reports.

“With polls showing Sen. Pat Roberts in serious trouble against independent Greg Orman, top Senate Republicans, including Minority Leader Mitch McConnell of Kentucky and Sen. Orrin Hatch of Utah, are leaning on big-ticket donors to fill the long-time Kansas senator’s campaign coffers. Sens. Rand Paul of Kentucky and John McCain of Arizona are planning to barnstorm the state on Roberts’ behalf. And in a bid to boost the senator’s sagging poll numbers, the Roberts campaign is planning an ad blitz to cast his long record and seniority in Washington in a more positive light.”

Sen. Ted Cruz (R-TX) “is continuing to send signals that he’s running for president,” Politico reports.

“The Texas senator’s chief of staff, Chip Roy, a former top hand to Texas Gov. Rick Perry, is leaving his role as chief of staff and will play a larger role in Cruz’s political office, according to an aide with knowledge of the changes. He will gradually transition from the congressional office to serve as a senior political adviser for Cruz.”

Larry Sabato: “For several months, we’ve held steady on our range of expected gains for Republicans in the Senate: a net of four to eight seats. With Labor Day in the rearview mirror and with less than 55 days to go until the midterms, we’re giving Republicans a slight bump: Our new range is a Republican net of five to eight Senate seats.”

“This means that the best-case scenario we can now envision for Democrats is a 50-50 tie in the Senate, with Vice President Joe Biden’s tiebreaking vote narrowly keeping Sen. Harry Reid (D-NV) as majority leader.”

“The likeliest outcome remains a Republican gain of six or seven seats, which we noted before Labor Day and stand by now. That would be good for a narrow 51-49 or 52-48 Republican Senate majority.”

The Hill: “Senate Republicans are brimming with confidence they will be in the majority next year — and say Democrats are beginning to acknowledge privately that harsh political reality.”

A new Magellan Strategies poll in Kentucky finds Sen. Mitch McConnell (R) leads Alison Lundergan Grimes (D) in the U.S. Senate race by eight points, 50% to 42%, with Libertarian David Patterson at 6%

A new Public Policy Polling survey in Iowa finds Joni Ernst (R) with a slight lead over Bruce Braley (D) in the race for Senate, 45% to 43%.

A new Quinnipiac poll in Pennsylvania finds Tom Wolf (D) has a commanding 24-point lead over Gov. Tom Corbett (R) among likely Pennsylvania voters with a little more than seven weeks until the election, 59% to 35%.