With Michigan’s governor looking on, President Barack Obama reauthorized an expanded health insurance program for children this afternoon, calling it a “down payment on my commitment” to ensure coverage for every American.

The $74-billion reauthorization of the state Childrens’ Health Insurance Program — representing an increase of about $33 billion over the next five years — represented what Obama called “one of the highest responsibilities we have.”

SCHIP already covers about 7 million kids; congressional estimates are that the additional money should allow the states to cover about 4 million more, including legal immigrant children in some cases. The House approved the legislation on a vote of 290-135 earlier today.

President George W. Bush had vetoed the expansion twice in the last Congress.

Obama said parents without insurance for their children are often forced into decisions they should never have to make — “how long to put off that doctor’s appointment, whether to fill that prescription, whether to let a child play outside, knowing that all it takes is one accident, one injury, to send your family into financial ruin.”

“This is not who we are,” added Obama. “We are not a nation that leaves struggling families to fend for themselves.”

Also attending the bill signing at the White House this afternoon from Michigan were Rep. John Dingell, a Dearborn Democrat, and U.S. Sen. Debbie Stabenow.

In Michigan, the additional funding could result in more than 71,000 additional kids receiving basic health care coverage, according to the Families USA, a health care advocacy group based in Washington, D.C. Right now, about 114,000 children in Michigan receive health care through Michigan’s SCHIP program, known as MiChild.

“Enactment of this bill represents a clear example of the change voters demanded last fall,” said Rep. Gary Peters, a Bloomfield Township Democrat who last fall defeated Republican Joe Knollenberg, who was criticized in some quarters for voting against the legislation last year. “Thousands of Michigan kids went without health care for years while Washington bickered.”

But there remained concerns that waivers to the states could result in them authorizing funding for children whose families would otherwise qualify for private health insurance. Midland Republican Dave Camp — the ranking Republican on the House Ways and Means Committee — said in some cases families making up to $88,000 a year could be eligible for free healthcare and that private coverage could be eliminated for some 2.4 million people. But while waivers could be granted to allow states to offer coverage to families making more, there is nothing in the legislation that requires it.

Among Michigan’s delegation, all the Democrats voted for the legislation, as did four Republicans — Candice Miller of Harrison Township, Thad McCotter of Livonia, Vern Ehlers of Grand Rapids and Fred Upton of St. Joseph. Voting against were Republicans Camp, Mike Rogers of Brighton and Pete Hoekstra of Holland.

In all Democrats voted 250-2 in favor of the bill; among Republicans, 40 were supportive and 133 against.

In Michigan, the program covers kids ineligible for Medicaid whose families have incomes less than twice the national poverty level — $44,100 for a family of four. And while Michigan’s program has provided coverage to childless adults with incomes of less than 35% of the poverty level — $3,790.50 — the legislation phases out that coverage (though it includes a provision to provide SCHIP coverage to pregnant women).

The legislation would be paid for through a 62-cent-a-pack increase in the federal excise tax on cigarettes, which would hike that tax from 39 cents a pack to $1.01. It also raises taxes on other tobacco products. The congressional Joint Committee on Taxation estimates that will increase federal revenues by $71.4 billion — covering most of the cost — during the next five years.