Republicans returned to Washington on Monday night in an increasingly dour mood about the state of their party: Growing fears of a November wipeout. A Middle East war with no end in sight. A feeling of loss after the sudden death of their longtime colleague Lindsey Graham. Now, with President Donald Trump’s attention focused on Capitol Hill for what could be the party’s final legislative sprint before the midterms, a restless House Speaker Mike Johnson is racing to reverse Republicans’ political fortunes. Johnson is privately pushing a major legislative push centered on Pentagon funding, cutting government fraud and a new...