Newly sworn-in Sen. Scott Brown (R-Mass.) will stump for the man he calls his "mentor," Sen. John McCain (R-Ariz.), in March.

Brown's surprise victory last month in the Massachusetts special election to replace the late Sen. Edward Kennedy (D-Mass.) has made him a hot commodity amongst Republicans.

The Arizona Republic on Friday first reported Brown's appearance.

McCain faces a primary challenge this year from former Rep. J.D. Hayworth, who is trying to outflank the veteran senator on the right.

But Brown, who was sworn in as the 41st GOP senator Thursday, could help McCain among those on the right; his candidacy was backed by a number of national conservative activists.

Here is more from the Republic:

The day after Brown's upset win, he recorded robocalls for McCain, who faces a potentially bumpy road to a fifth term this year. McCain, R-Ariz., was an early supporter of Brown's.

"When few thought I had a chance of winning, John stood by me and supported my campaign. He was the first one," Brown said in the Jan. 20 robocall. "I want to thank him for his support for me and I want to encourage you to continue to support John. I look forward to joining him as he fights against wasteful spending and a government takeover of your health care."

McCain's running mate from the 2008 presidential campaign, former Alaska Gov. Sarah Palin (R), will also campaign for McCain in late March.

Palin is also a favorite of conservatives.