Live updates: Canada tariffs hit back against Trump; New Hampshire votes in Senate primary elections

What to know today NEW HAMPSHIRE PRIMARIES: In New Hampshire's Senate primary today, former Sen. John Sununu is running in a GOP field that includes another former senator, Scott Brown, while on the Democratic side, Rep. Chris Pappas is looking to fend off democratic socialist opponent Karishma Manzur. DEEP DIVE: New Hampshire is not expected to be a key Senate battleground this fall, but Republicans have their fingers crossed for a democratic socialist victory that would scramble that thinking. NBC News' chief data analyst Steve Kornacki breaks down the race in his new subscriber-exclusive newsletter, The Data Dive. TRADE WAR INTENSIFIES: President Donald Trump said Canadian aerospace company Bombardier should no longer be allowed to sell its planes in the U.S., opening a new front in his trade war as new Canadian tariffs on American goods take effect. 'NEW AMERICA' PUSHBACK: New Mexico Democratic leaders are aggressively pushing back on Trump’s social media posts over the long Labor Day weekend about renaming the state of New Mexico as “New America.”

Live updates and the latest news as New Hampshire voters to decide Senate general election matchup, Trump posts about renaming New Mexico “New America,” the U.S.-Canada trade war escalates.