Rep. Chris Pappas (D-N.H.) is telling his colleagues that he'll announce his campaign for New Hampshire's open Senate seat early next month, according to people familiar with the matter. Why it matters: Pappas wants to put down a marker he'll run to succeed retiring Sen.

Four-term Congressman Chris Pappas of New Hampshire has announced his bid to succeed retiring U.S. Sen. Jeanne Shaheen, a fellow Democrat, next year